The ultimate goal of this line of research is to optimize quality of life and minimize disability for people with dysvascular lower limb amputation through improved physical activity self-management. An initial step toward that goal is to test our walking biobehavioral intervention. Our overarching hypothesis is that implementing walking biobehavioral intervention for people recovering from dysvascular lower limb amputation, a disease characterized by multiple chronic conditions, will improve health self-management, as measured by increased habitual physical activity. The complex, comorbid nature of dysvascular amputation requires extended healing time and unique approaches to recovery compared to amputation from traumatic causes. Chronic sedentary behaviors that are present before amputation become more obvious when compounded by the effects of limb loss. As a result, people with dysvascular amputation report extremely high disability and walking limitation as their number one functional problem. Biobehavioral intervention integrated within conventional prosthesis rehabilitation is an opportune time to address walking behaviors by capitalizing on motivation for change. However, prosthetic training guidelines do not include walking biobehavioral intervention. Therefore, the purposes of this Phase II clinical trial are to: 1) test the benefit of walking biobehavioral intervention for improving habitual daily walking activity and 2) determine the potential for implementing the walking biobehavioral intervention in rehabilitation by performing initial assessments of intervention reach, efficacy, adoption, implementation, and maintenance. This trial presents an alternative strategy for improving quality of life and reducing disability in an underserved, medically complex, chronic disease population. The trial is directly aligned with the NIH Funding Opportunity Announcement PA-18-146, which seeks clinical research on self-management interventions that improve quality of life in persons needing assistance to optimize function, prevent/delay disability, and navigate their environment.